Abstract:
Atom probe tomography (APT) is a burgeoning materials characterization technique that enables elemental mapping in three-dimensions at the nanoscale and with high elemental sensitivity. APT exploits the effect of an intense electrostatic field to cause the departure of individual atoms, in the form of ions, from the end of a very sharp needle-specimen. The very particular geometry of the specimen gives rise to a highly magnified image formed by the projected ions by the electric field itself. This projection microscope is then coupled with a time-of-flight mass spectrometer to reveal the elemental identity of each of the detected ions. In this presentation, I will cover briefly some of the fundamentals of APT, laying out some of the challenges of atom probe research, as well as highlight the strength of the technique by showcasing some applications to investigate phase transformations and segregation phenomena in a variety of metallic and semiconductor systems.
Biography:
Dr Gault currently holds a joint appointment between Imperial College London and the Max-Planck-Institut für Eisenforschung in Düsseldorf, where he is the Group Leader for atom probe tomography. Since Feb. 2018, he also leads an ERC-Consolidator funded group, targeting hydrogen in metals using atom probe tomography. Dr Gault obtained his PhD in physics in Rouen (Feb. 2007) where he developed a new generation of pulsed-laser atom probe microscopes. He then worked as a research scientist at the Australian Centre for Microscopy and Microanalysis at the University of Sydney from 2007-2009 and 2010-2012 (jointly with ANSTO). In between, he held an Intra-European Marie Curie fellowship at the Department of Materials, University of Oxford where he worked on thermoelectric materials. In 2012, he started a brief academic appointment as Assist. Prof. at McMaster University in Canada. From Dec. 2012 to Dec. 2015, he interrupted his research career, and took on a position of Senior Publisher in the Materials Science group at Elsevier Ltd. in Oxford, looking after the Materials Engineering portfolio that comprises Acta Materialia & Scripta Materialia.Since April 2013, he is also an academic visitor at the Department of Materials, University of Oxford. He became Group Leader at the Max-Planck-Institut für Eisenforschung in January 2016.